Bang for your buck XT has always been very good but without that big Eagle gear its been at a disadvantage for a few years. We’ve been patiently waiting for the new Shimano XT M8100 12 speed and finally have some miles under it to give some thoughts. Sram Eagle’s super wide range 10-50 Eagle has been soaring on my bikes the last few years. Now that XT has the 10-51 cassette Shimano appears to again be a strong option.
At this time there isn’t much info about the new group. That is unless you consider a bunch of magazine editors that were all flown out to the same product launch by Shimano that all rode bikes set up and dialed by Shimano on a ride or two. With the complete install of a couple of XT 8100 12 speed groups and some good saddle time here are my thoughts.
Quick Comparisons to Sram Eagle
- The precision and quality of the new XT is very good – more closely comparable to XO1 even though it’s half the price. The shifting is especially smooth and quiet – one of my riding buddies commented that he didn’t hear me shifting while he was riding behind.
- Weight-wise, the XT 8100 group is almost identical to Sram GX Eagle. XT maybe around 25 – 50 grams less depending on options. Sram XO1 is about 225 grams or 1/2 lb lighter than XT.
- XT 8100 can shift 2 gears down (harder) with a full push of the lever and 4 gear up (easier) with a full push of the lever. Sram allows for only one shift down but 5 shifts up with a full stab. I like the light action of Sram for the downshift, but I do sometimes bump the lever by accident causing an unwanted shift into a larger gear.
- Cranks – Shimano BB preload adjustment with the little $2 tool is quite simple allowing for easy installation and removal. Sram’s latest DUB BB has the preload adjuster made into the system so you don’t need a special tool but removing cranks is a different story. I’ve had a couple of sets of DUB cranks that I had a real hard time removing. I couldn’t budge the 8mm self-extracting crank bolt with a 3-foot breaker bar. I had to use an impact wrench and even with the powerful impact wrench removal wasn’t a breeze.
- Price: Shimano XT M8100 is only about $50 more than Sram GX Eagle, but half the price of Sram’s XO1.
Test Group Details:
Shimano XT M8100 12 Speed | $600 – complete drivetrain with cranks + $154/per brake | 10-51 cassette | 175mm cranks 32 tooth | 2 piston brakes w/ 180mm rotors


The XT 2-piston brakes with 180mm rotors offer plenty of stopping power for the intended use of the Ibis Ripley test bike and my 150 lbs. I feel the modulation is excellent with a hard bite if you need it. The changes seem pretty minimal except for the repositioning of the clamp and brace. The brace or tab rests on the bar closest to the grip.

The good and the not so good
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- Smooth shifts both up and down throughout the range with no noticeable big transitions
- Precise feeling – very smooth and positive
- Excellent bang for your buck
- Reasonable cassette price when you have to replace – $115 XT 8100 – $215 for Sram GX Eagle
?
- No cage lock on the derailleur to take complete tension off for wheel removal/installation
- Cassette is a little more cumbersome to install – not too hard but just have to line up the smaller cogs perfectly or risk cross-threading the lockring
Final Thoughts
It may be too early to speak on long term use but If the new Shimano XT8100 is like previous generations, its durability will be rock solid. Overall I am SUPER happy with the new XT M8100 group and feel its a great alternative to Sram XO1 Eagle at half the price if you can deal with the added 250 grams. With that said the differences between the groups are very small and likely a hardcore Sram fan will still be a Sram fan. The Shimano XT M8100’s extra gear and nice refinements help the group regain its strong bang for your buck heritage.
This Post Has 3 Comments
Nice review but you have your upshifts and downshifts backwards. It is a down shift when you go into an easier gear and an upshift when you go into a harder gear. It’s just like a car or motorcycle.
I understand your logic there. Thanks for pointing that out! My choice of words might not have been the best for everyone, but it comes from the actual movement of the bike drivetrain – the shifter moves the derailleur up or down the cassette.
I agree with the previous comment. Upshifting is going to a harder/higher gear, while downshifting is the opposite, just like a car, semi, motorcycle, etc.
Your explanation referring the the “visual” movement of the chain on the cassette may seem to make sense at first, but actually doesn’t when considering that many people still use a 2X or 3x setup, in which case the “visual” Down or up movements will give the opposite result as the cassette.
It’s more logical to use words as they’re already understood, rather than creating your own contradictory version, unless your goal is to be less clear.